GOLDEN AGE COMP54 Compressor

The Golden Age COMP-54 is a one-channel vintage-style compressor. The signal path uses only discrete components like resistors, capacitors and transistors. The line input and output are transformer balanced and the unit also has a third interstage transformer.

The class-A circuit used in the COMP-54 is similar to the one in the classic 2254 compressor that was designed in 1969. It quickly became a legend due to it´s totally unique sound character that is warm, smooth, sweet and musical. These characteristics have been heard on countless recordings through the years and it is a versatile sound that works very well on most sound sources and in most genres. The essence of this sound is now available at a surprisingly low cost, making it available to nearly everyone.

The COMP-54 uses a diode bridge as the gain control element, a method that is revered for its smooth way of operation. Some of the most sought after vintage compressor designs, like the 2254, 2264, 33609, Siemens and EMI used the same basic design.

The controls in the COMP-54 are very flexible covering broad ranges of Ratio, Attack and Release times, including two Auto positions. All controls except the Gain make-up one are stepped for easy resetting and stereo matching.
There are three selectable sidechain high pass filter frequencies available to handle special situations.

The Bypass switch is a true bypass where a relay switches the complete circuitry in or out. The IN/OUT switch makes it possible to switch the compression on and off while retaining the coloring from the transformers and the electronic circuitry.
The meter can show output level or gain reduction. It is also possible to link two units for stereo operation.
Features

• Vintage-style electronics
• Based on classic diode-bridge designs
• Transformer-balanced I/O
• Transformer upgrade (Carnhill) available
• Flexible control of Ratio, Attack and Release
• Stepped controls (except Gain make-up) for repeatability
• Three selectable Sidechain filter frequencies
• Separate Bypass and Compression In/Out switches
• Meter selectable for Output and Gain Reduction
• Link two units for stereo operation
• Separate input/output XLR and TRS jacks for flexible connection
• Back-panel switch for 600 ohm termination.
• External power power supply to avoid interaction with the audio circuitry and transformers.
• Great sound that suits most sound sources and genres

Description

The alphaton Feedback-Controller FC-100 is a revolutionary product for every microphone
application including wireless types. It can provide effective feedback control to any sound
reinforcement situation. It can also eliminated string feedback in guitars and bass instruments
which are equipped with piezo or condenser pickups.
The FC-100 provides 6 to 10 dB of feedback protection by analysing the incoming signal,
detecting the presence of feedback and then notching out the feedback frequency.
The FC-100 relieves the sound engineer automatically. It works dynamically and eliminates a
feedback signal before it can grow into a peak. Internally a discriminator circuit detects the
presence of regenerative feedback and triggers the automatic equaliser to insert a notch where
the feedback peak is coming up. This normally prevents other peaks from developing but if they
do, the process is repeated at high speed, thus keeping feedback under control.

Technical Data
In- and Outputs transformer balanced
max. Inputlevel + 3 dB
Gain (RS=200 Ohm, RL=2kOhm) 0 dB
Frequency Response 20 Hz ... 20 kHz, +/- 1,5 dB
Feeback Cancellation  6 ... 10 dB
Power Requirement  30 ... 48 V Phantom
Current drain ca. 8 mA
External Power Supply 9 ... 20 V DC, 3,5 mm jack, tip +
Housing Aluminium Diecast
Weight  285 grams
Dimensions  112 x 60 x 32 mm

The Multicom Pro-XL MDX4600 gives you 4 channels of first-class dynamic
control in a single rack space. With a multitude of new features like the
advanced program-adaptive expander gate, extensive metering plus a variety
of configuration options, the Multicom Pro-XL puts a lot of dynamic processing
power in your rack.

Features
Switchable IKA (Interactive Knee Adaptation) program-adaptive compression
circuitry combines the advantages of hard-knee and soft-knee characteristics
IRC (Interactive Ratio Control) expander/gate circuitry for virtually inaudible noise
suppression
Switchable dynamic enhancer for brilliant, lively audio even with heavy compression
IGC (Interactive Gain Control) peak limiting circuitry combines clipper and program
limiter for reliable and inaudible protection against signal peaks
Switchable low contour filter prevents "pumping" due to low-frequency dominated
compression
Stereo couple function selectable for channels 1/2 and 3/4
Ultra low-noise 4580 operational amplifiers and state-of-the-art THAT¬ VCA's
Separate 8-segment LED meters for input/output levels and gain reduction
Selectable operating level (+4 dBu/-10 dBV)
High-quality detented ALPS¬ potentiometers and illuminated switches
Servo-balanced inputs and outputs with ? in. TRS and gold-plated XLR
connectors
Manufactured under ISO9000 certified management system

Innovation

The ARX AFTERBURNER? is a unique Multi Mode compressor/limiter
designed for use in any professional audio dynamics control application.
Multiple Modes
The Afterburner can be set up and used in three different ways:
In Two channel mode, it performs as two independent compressor/limiters,
with 'industry standard' variable Threshold, Ratio and Output gain. In stereo
mode, our New Adaptive Stereo Link circuitry provides increased stereo
imaging accuracy when linking both channels as a stereo pair. A single front
panel switch puts the Afterburner into its alternative Mono mode, setting it up
as a Single channel, Dual Band compressor/limiter, with separate dynamics
control of both Low and High frequencies, opening up a whole new range of
gain control techniques.
Enhance Switch
In any mode, the Afterburner features an 'Enhance' switch, which provides
frequency restoration to preserve the spectral balance of the audio signal,
compensating for the sagging Low and High frequency response of compressed
program material. Think of it as a 'smart' loudness control.
 
Features
Switchable Modes - Stereo; Dual Channel Single band; or Single Channel
Dual Band (Low and High)
Low and High frequency compression in Single Channel mode
'Enhance' switch restores spectral balance of compressed signal
New Hard/Soft knee compression switch
New Adaptive Stereo Link circuit for accurate stereo imaging
New Above/Below Threshold LEDs enable at-a-glance compression
confirmation
Balanced XLR and Jack Inputs and Outputs
Sidechain Insert points
Intuitive user-friendly layout
Flawless performance
 
New Above/Below Threshold LEDs enable at-a-glance compression confirmation
New Hard or Soft knee compression option
New LED metering provides accurate Level status, with separate Gain Reduction
metering in easy to read 'wide scale' meters. There is also comprehensive LED
indication of all operating functions and status in any mode.
Balanced Inputs and Outputs
On the rear panel, each channel has true differential Balanced inputs and outputs,
on both XLR and TRS jack connectors. As well, each channel has a TRS jack
Sidechain access insert point, for applications such as De-essing (when used with
an external equalizer such as the ARX Multi Q or EQ 260).Other features include a
true Hardwire bypass switch for each channel, and passive RFI filters on the inputs.
Universal AC Power
AC power range is a universal 100 to 120V or 220 to 240V AC, and is connected to
the unit via a removable power lead and standard 3 pin IEC connector, with built-in
fuse and voltage change switch.
With its smooth compression, intuitive user friendly layout, high density precision
circuitry, and extensive user-variable operating parameters, the unique ARX Afterburner
is equally at home in Studio, Installation, Broadcast and Sound Reinforcement
environments. It can provide great sounding dynamics control effects that are not
available with any other device.
 
T E C H N I C A L  S P E C I F I C A T I O N S
Input Impedance Balanced 20 Kohms, Unbalanced 10 Kohms
Input Headroom + 22 dB
CMRR >60 dB, 20 Hz-20 KHz
Output Impedance Balanced 300 ohms, Unbalanced 150 ohms
Output Level (Max) + 22 dB
Frequency Response 20Hz to 20KHz ±0.2dB
Signal to Noise ratio -93 dB Unweighted, -99 dB 'A' weighted
Distortion .02% THD @ 0dB,1KHz
Dynamic Range 115 dB
Sidechain Insert Impedance 10 Kohm
Filter Section
Filter Type Phase corrected 6dB/octave
Summed Filter Response ±0.2dB through crossover region
Dividing Frequency 250 Hz
Enhance Section
Low Enhance 50 Hz, High Enhance 10 KHz
Power Requirements 100/120 V AC, 220/240 V AC
Weight 5 lbs/2.2 Kg
Dimensions 19“W x 1?“H x 6“D, 482 x 44 x 155mm
Input/OutputConnector type XLR, Balanced Jack
Sidechain Insert Connector TRS Jack

Front Panel Controls
Hardwire bypass IN/OUT switch
Threshold, Ratio and Output Gain controls
Above/Below Threshold LEDs
12 segment LED Output Level display
Numbered marker panel for labelling compressor assigns
7 segment LED Gain Reduction display
Enhance switch and status LED
Adaptive Stereo link switch and status LED
Dual/Single channel mode switch and status LEDs
Rear Panel Connectors
Balanced Inputs and Outputs, on both XLR and TRS jack
connectors. In Single channel (Mono) mode, use Channel
1 Inputs and Outputs only
Sidechain Insert TRS connector on each channel
AC input connector, with voltage switch and fuse.
 

The Avalon VT-737SP features a combination of TUBE preamplifiers,
opto-compressor,sweep equalizer, output level and VU metering in a
2U space.
PREAMPLIFIER
The VT-737SP has three input selections: 1. The VT-737SP features a
higher-performance microphone input transformer with +48v phantom
selection. 2. Instrument DI high source input with jack located on front
panel. 3. Balanced line input, discrete high-level Class A. The Class A
preamplifier utilizes two cascaded, dual vacuum tube triodes configured
with minimum negative feedback. A high gain switch boosts the overall
gain of the preamplifier. The four high quality tubes are configured as
singled ended anode coupled followers. A passive-variable high pass filter
and hard-wire relay bypass completes the input signal conditioning. The
phase reverse relay is available on all three inputs.
OPTO-COMPRESSOR
The opto-compressor features a minimum signal path design with twin Class
A vacuum tube triodes for gain matching. The optical attenuator acts as a
simple passive level controller. Full dynamic control from soft compression to
hard- knee limiting can be achieved with threshold, ratio-compression, attack
and release controls plus gain reduction selection on the large VU meter. Special
spectral control including de-ess is available with the dual sweep mid EQ to side-
chain switch. The EQ section can be flipped pre or post the opto-compressor
via a front panel switch for alternate effects and tone shaping. Two VT-737SPs
can be linked via a rear panel link cable for stereo tracking. The compressor
bypass is a sealed silver relay for the most direct signal path.
SWEEP-EQUALIZER AND OUTPUT LEVEL
The VT-737SP equalizer utilizes 100% discrete, Class A-high-voltage transistors
for optimum sonic performance. The high and low frequency bands provide the
smooth characteristics of an all passive design, while the dual mid bands include
variable frequency and switched Q-width selection. The enhanced range of the mid
bands is extended into the high and low bands by the use of X10 frequency multipliers.
The bypass switch incorporates a sealed silver relay for the most direct signal path.
When the EQ to sidechain is engaged, the high-low EQ remains in the audio path for
"tone enhancement“. The output level control provides a variable control of the overall
signal path. The output amplifier utilizes another dual triode vacuum tube driving a
100% discrete, Class A, high-current, balanced and DC coupled low noise output
amplifier.

AVALON VT-737SP FEATURES
Vacuum tube triode signal path, transformer balanced microphone input, high-voltage
circuits for maximum headroom to +30dB, low noise -92dB, internal discrete power
supply with toroidal transformer, soft-start tube life extender, stereo link for compressors,
all discrete Class A equalizer with musical passive filter design, sealed silver relays for
signal routing, large control knobs with professional conductive plastic potentiometers,
VU meter for output level monitoring and compressor gain reduction.

VT-737SP SPECIFICATIONS
Circuit topology Four dual triode vacuum tubes (Sovtek 6922), high-voltage discrete
Class A
Gain Range Microphone: Transformer balanced 850/2500 ohm, 0dB to +58dB Instrument:
Unbalanced 1 meg ohm, 0dB to+30dB Line: Balanced Class A 20k ohms, -27dB to 28dB
Maximum input level and connector types Microphone26dB@25Hz, +30dB@1kHz balanced
XLR Instrument+30dB unbalanced front panel jack socket
Line +36dB balanced XLR
Maximum output level +30dB balanced 600 ohms, DC coupled, discrete Class A
Output type and gain XLR connector, output trim gain -45dB to20dB
Noise 20kHz unweighted -92dB
Noise microphone EIN -116dB, 22Hz to 22kHz unweighted
Distortion THD, IMD 0.5%
Frequency response -/2.5dB 10Hz to 120kHz input filter included
Frequency response -3dB 1Hz to 200kHz line in-out
VU meter and gain reduction High quality illuminated OVU =+4dB and gain reduction to -20dB
High cut filter Variable 6dB per octave 30Hz to 140Hz
Compressor type Optical passive attenuator incorporating twin vacuum tubes and stereo link
Threshold - Ratio Threshold variable -30dB to +20dB, ratio-compression variable 1:1 to 20:1
Attack - Release Attack variable 2mS to 200mS, release variable 100mS to 5 seconds
Equalizer type Discrete Class A, variable active and switched passive design
Frequency bands (4) Treble - switched 10kHz, 15kHz, 20kHz, 32kHz, +/- 20dB range, shelf
High mid - variable 200Hz to 2k8Hz and 2kHz to 28kHz, +/- 16dB range, hi-lo Q Low mid -
variable 30Hz to 450Hz and 300Hz to 4k5Hz, +/- 16dB range, hi-lo Q Bass - switched 15Hz,
30Hz, 60Hz, 150Hz, +/- 24dB range, shelf
AC power Internal toroidal 100v to 240v, 50-60Hz selectable, 75 watts maximum
Dimensions 19 x 12 x 3.5 in (482 x 305 x 89mm)
Weight 22lbs (10kg)
Dimensions-shipping carton 21 x 18 x 8 in (533 x 457 x 203mm)
Weight-packed 26lbs (11.8kg)